Toothbrushes are known articles, generally comprising a head and a grip handle, disposed along a longitudinal head-handle direction, with a neck longitudinally in between the head and handle. The head is generally elongate between a tip distant from the handle and a base closest to the handle, and is flattened in its thickness direction generally perpendicular to the longitudinal direction, and has a widthwise direction perpendicular to both the longitudinal and thickness directions.
The head normally has a face from which one or more oral hygiene parts such as tooth-cleaning parts, e.g. bristles project in a bristle direction generally perpendicular to the longitudinal direction, and an opposite face, these faces being joined by edge surfaces. As the face is normally generally planar bristles project in a bristle direction generally perpendicular to the face. The head may be an integral part with the handle, or may be replaceably attachable to the handle or handle-neck unit. Toothbrushes are generally made from hard plastics materials such as polypropylene, but many these days are two-component, i.e. having a hard plastics skeleton and one or more softer elastomeric parts e.g. to enhance the grip handle and/or to provide elastomeric parts of flexible links. Among such two component toothbrushes are the applicant's Dr BEST™ and AQUAFRESH™ range of toothbrushes.
Toothbrushes having elastomeric oral hygiene parts on their head to contact the teeth and gums are known. The term “oral hygiene part” as used herein refers to a part which contributes to oral hygiene, for example by cleaning the teeth, gums or other oral tissues, and/or massaging the gums or other oral tissues. GB-A-2 040 161 discloses longitudinally extending elastomer strips. GB-A-2 214 420 and WO-A-00/49911 both disclose a toothbrush having a head from which project small rubber pyramids. GB-A-214 701 discloses a toothbrush having oral hygiene parts comprised of strips of crepe rubber, in one theoretically discussed embodiment of which the strips may have bristles sandwiched between the strips of crepe rubber. EP-A-0 360 766 discloses small rubber cylinders with knobbed ends. U.S. Pat. No. 4,128,910 discloses a toothbrush having rubber oral hygiene parts of various pyramid and ridge shapes. U.S. Pat. No. 4,277,862 discloses a toothbrush having resilient gum massage parts along the outer edges of the bristle pattern. U.S. Pat. No. 4,288,883 discloses rubber cones. U.S. Pat. No. 5,040,260 discloses a toothbrush having a head from which extend small rubber cones. WO-A-96/15696 discloses a toothbrush head provided with strips of a flexible and resilient material, typically a non-elastomeric nylon material, and typically aligned either perpendicular to or parallel to the longitudinal direction. WO-A-96/28994 discloses elastomer bars extending perpendicular to the longitudinal direction and parallel to the edges of the head in combination with bristle “bars” having an elongate cross section cut across the bristle direction, and also discloses a curved rubber “scooping bar” at the tip end of the head. WO-A-97/16995 discloses elastomer “bristles”. WO-A-98/18364 discloses tooth polishing pads or finger-like structures. WO-A-99/37181 discloses an outer ring of rubber fingers surrounding an inner dense pack of bristles. WO-A-00/64307 discloses rubber bars with a generally triangular cross section. WO-A-00/76369 discloses elastomeric massaging parts with rotational symmetry through an angle of 120° or less e.g. cylinders. WO-A-01/21036 discloses a longitudinally extending elastomeric wall-like member running for at least half the length of the head.
Such elastomeric parts are provided inter alia to massage and/or stimulate the gums and to clean the teeth and gums. Often they are provided on a toothbrush head in a cluster together with conventional bristles, e.g. made of known nylon materials, to supplement and enhance the tooth and gum cleaning effect of the bristles.
“Flexible head” toothbrushes are also known with two or more flexibly and resiliently linked segments in their head, i.e. a “multiple segment” head, see for example WO-A-92/17093, WO-A-96/02165, WO-A-97/07707 and WO-A-97/24048. It is also known to provide toothbrushes with a head which is connected by a flexible link to the handle, see for example WO-A-92/17092 and WO-A-97/24949. It is also known to provide toothbrushes with a head which is connected by a flexible link to the handle, and which also has two or more flexibly and resiliently linked segments in its head, see for example WO-A-98/37788.
The content of these patent publications is incorporated herein by reference.